All, just dismantled my 1981 xj550 uk spec engine 4v8 ?? Standard I had hoped it would be standard bore of 57mm and i would hone/ deglaze the bores fit new rings do a valve refurb and rebuild. I measure the bore and Piston diameter and find it to be 59 mm. Is this possible as all imfo i read over here is max bore is 1 mm oversize . I.e 4 times 0.25 mm I wonder if anyone can help or do i look for second hand cylinder block . As you are aware this model was not a big seller in uk compared to US/ Canada so parts rare second hand and carraige costs on large parts from N America are prohibitive. Look forward to any reply that may help.